Serpae Tetra 101: Care, Diet, Tank Size, Tank Mates, & More

Species Summary

A wonderfully playful fish and beautiful in appearance, the Serpae Tetra has become a favorite among aquarists looking to spruce up their tanks with a bit of joie de vivre and color.

Their binomial name is Hyphessobrycon Eques; however, with that being a rather obtuse title, they’re also referred to as Red Minor Tetra, Jewel Tetra, or Callistus Tetra. Pertaining to the family of tropical, freshwater fish, Characidae, you’ll find them swimming up a storm in the drainage of the Amazon River. 

Care Guide

Serpae Tetra are easy-going fish. They don’t require any military-grade organization to keep them healthy, happy, and floating the right way up. That being said, you will still need to know the basics if you want them to thrive in your aquarium.

Tank Size

Tropical fish are usually pretty finicky about the size of their habitat, but due to the Serpae Petra’s diminutive stature, it really doesn’t need a full-blown aqua-penthouse. That said, they are adventurous souls with a lust for life and adventure.

A 20-gallon tank lets them live out these adventures without restrictions.

Tank Mates

Serpae Tetra appreciate speed, agility, small stature, and a peaceful disposition in a tank mate.

Slower fish may end up on the receiving end of the odd fin nip, so it’s best to stick to the snappier species. Bring in too large of a friend, and your poor little Serpae Tetra may end up as dinner, which would be tragic.

Some fish that make particularly great Serpae Tetra chums include…

  • Cory Catfish
  • Pictus Catfish
  • Twig Catfish
  • Bloodfin Tetra
  • Cardinal Tetra
  • Black Skirt Tetra
  • Swordtail Fish
  • Bolivian Ram Cichlid
  • Bristlenose Pleco

…Or a particular favorite among aquarists, the Celestial Pearl Danio.

Same Species Tanks

Serpae Tetra are incredibly social with their own species, so feel free to raise them in groups of 5-7. In fact, there really are no better tank mates for them than more of their own.

You may notice some mild aggression from time to time, but that’s just because they’re naturally inclined to form a pecking order.

Fish higher up this pecking order will nip at their underlings from time to time, but it’s usually nothing to worry about. However, if you ever become worried that the higher-ups are getting too aggressive or hogging food, they need to be removed from the aquarium. 

Water Parameters

Remember earlier when I mentioned that the Serpae Tetra are native to the Amazon River drainage basin? Well, that means that their natural habitat is warm, soft, calm, slightly acidic, and murky to the point of blackness.

That’s not to say you have to dirty up your aquarium water to make them feel at home; you want to be able to see these magnificent fish, after all. But getting the right temperature, hardness, and PH is essential. The ideal water conditions for Serpae Tetra are as follows…

  • Temperature: 72 – 79° F (22.2 – 26.1° C)
  • pH: 5 – 7.8
  • Water Hardness: 5 – 25 dKH

There’s some pretty significant wiggle room in there, which is why Serpae Tetra are suitable for novice fish-keeping hobbyists, but one thing to bear in mind is that they’re incredibly sensitive fish.

They’ll pick up any recent overhauls in water conditions, so it’s best to establish the water condition well in advance of introducing them to the tank.

What to Put in Their Tank?

Here’s where the creative fish-keepers will really shine. The goal with the decor of your Serpae Tetra tank is to recreate the Amazon River Basin as accurately as possible.

Although you might not be able to peer through the adamantine darkness of this murky body of water, what lurks beneath is vegetation, vegetation, vegetation!

But before you introduce some plants to your aquarium, you should start by choosing a dark substrate. Black or dark gray sand is just the ticket, as it mimics the fine layer of decomposing plant matter found on the bed of the Amazon River Basin.

With your foundation set, we can add some greenery. Myriophyllum and Java moss are great choices, as they offer plenty of shelter without restricting movement too much. Your Serpae Tetra will be happiest when they can navigate the leaves of a plant easily.

Plantlife serves two major Serpae Tetra purposes in the wild. It offers cover for socializing, and it’s also a source of sustenance, so be generous with your green additions.

In captivity, greenery also has a third purpose, and that’s to block out light. Serpae Tetra are accustomed to living in darkness, so bright lights can be disorienting for them.

Try to keep most of your vegetation to the edges of the tank, as although Serpae Tetra love dense submarine forestry, they need plenty of central room to stretch their fins and burn off some of that near-endless energy.

Now’s the time to add some finishing touches. A bit of driftwood here and a rock formation there will diversify the habitat and greatly enrich your Serpae Tetras’ lives.

In terms of filtration, you don’t need anything too specific. Standard canister filtration is fine, as are hang-on-back units. The only thing to be wary of is finding the right power balance.

Serpae Tetra are accustomed to calm waters, and a super-powerful return tube will cause too much turbulence, yet you need your filter to be powerful enough to fully cycle the tank.

If you’re worried that your return tube is a little too forceful, try disrupting its output with some greenery.

Common Diseases

You’ll be happy to hear that Serpae Tetra aren’t genetically predisposed to any diseases. Just keep an eye out for the common freshwater ailments, such as Ich, skin flukes, and fungal infections.

As long as you follow a proper fish care and tank maintenance routine, the chances of your beloved fish family falling ill are very slim. Keep a close eye on those water conditions and everything should be fine.

Food and Diet

Serpae Tetra are omnivores, so they’re not too picky when it comes to dinner time. In the wild, they’ll nibble on vegetation and any insect larvae they can find floating on the water’s skin.

You can use a high-quality flake or pellet as the core of their diet, but I’d recommend introducing some protein-rich snacks too, such as bloodworms or brine shrimp.


Serpae Tetra tend to live between 5-7 years, which is a relatively good innings for a small fish. On occasion, some owners report that their Serpae Tetra exceed the 7-year mark; however, in suboptimal conditions, their life expectancy plummets.


While they’re quite a flat fish, Serpae Tetra have a tall profile, which is part of why they’re such an entrancing visual spectacle. Trapezoidal in shape, their color ranges from an olive-brown to a flamed crimson, and their scales shimmer in the light. The vibrancy of their base color will intensify with good diet and optimal living conditions.

One of their most distinctive features is the shark-tooth-shaped black marking behind their gills, but it’s common for it to fade as these fish grow older. They also have a large, beautiful, squared-off dorsal fin with black coloring and sometimes a white fringe.

While their anal fins mostly show the fish’s base color, the outer edge has the same black and white appearance as the dorsal fin.


You can expect your Serpae Tetra to reach around 1.75”, but there have been rare instances of them reaching 2” in length.

Behavior and Temperament

Mostly peaceful fish, Serpae Tetra spend their time in the middle and base of the tank, only really heading to the surface at feeding time.

They’re renowned fin nippers, but as long as you choose their tank mates carefully, this rarely becomes an issue.

Despite their elegant form, their swimming formations can be quite jerky, and while it’s less hypnotic than the silken form of other fish, it can be far more interesting to observe.

Alone, they’ll spend a lot of time in hiding, but in groups, they become more confident and enjoy exploring the farther reaches of the tank with their fishy friends.


Breeding Serpae Tetra is easy, but you’ll need a separate tank, as they tend to try and eat their own eggs shortly after fertilization.

When in labor, the female fish is chased by the male while she scatters hundreds of eggs throughout the environment. As such, it’s a good idea to decorate the breeding tank with lots of vegetation and perhaps even breeding mops to catch and protect the eggs.

The male will then fertilize the eggs, at which point it’s time to put the adults back in their normal tank.

To trigger breeding in this species, the water needs to be warm; anything up to 80° F is fine. The pH should be around 6.0, and it’s a good idea to load their diet with protein before transferring them to the breeding tank.

The eggs will hatch after two days or so, and the fry will devour their egg sac to grow stronger. Wait until they’re swimming with confidence, then introduce some baby food like shrimp, baby brine, or infusoria.

Young Serpae Petra must remain in the breeding tank until they’re large enough to fend for themselves and consume adult flakes.

Gender Differences: Male vs Female

The female fish can appear less vibrant and sometimes plumper than the males. Other than that, there’s little else we can do to tell the sexes of Serpae Tetra apart.

Fun Facts

  • The Serpae Tetra is a low-maintenance fish, making them a great choice for novice fish-keepers.
  • They’re consummate fin nippers, which can cause problems during socialization with other fish.
  • They form a pecking order within a group, similar to chickens.
  • Their color becomes more vibrant the happier and healthier they are.